“But to him that worketh not, but believeth on him that justifieth the ungodly, his faith is counted for righteousness.” (Romans 4:5)
The sinner can only be declared righteous by believing on Him who has the power to justify. The absence of works does not forbid a repentant attitude. Some have attempted to dismiss repentance in salvation, claiming that it qualifies as a work. This is not biblical thinking. God demands a change of mind toward sin (Isaiah 55:7), and this change of heart toward one's direction will undoubtedly affect the attitude and behavior to some degree. This verse is not forbidding the expression of repentance; it is condemning the man who believes he can live well enough to be accepted by God.
“Even as David also describeth the blessedness of the man, unto whom God imputeth righteousness without works, Saying, Blessed are they whose iniquities are forgiven, and whose sins are covered. Blessed is the man to whom the Lord will not impute sin.” (Romans 4:6-8)
This passage is a quotation of Psalm 32:1-2. In this Psalm, David is found making full confession to God for sin he had been harboring. This may have been his sin with Bathsheba and the subsequent murder of Uriah. Be that as it may, David is rejoicing in the weight which was removed upon confession before God. As long as man continues in self-justification, the weight of his actions will continue to increase; however, when a man will humble himself and confess his own failures as well as God's righteousness, he finds peace. The word for blessedness has the meaning of happiness. The word for iniquities literally means without law. It is a happy thing to have one's lawless behavior completely forgiven as well as sin covered in the blood of Christ. The last verse is particularly interesting. The phrase will not is a double negative in the Greek text. English does not use this structure, because in the English language, two negatives would make a positive; however, in biblical Greek, two negatives make an even stronger negative. Thus, the idea of impossibility is expressed. The Lord will, under no circumstances, ever impute sin unto the one who comes to him in repentant faith. David found it to be so. He fully turned his heart from sin unto God and found forgiveness and justification, regardless of how severely he had broken God's commands. This grammatical structure of the double negative bears witness to the doctrine of eternal security. Regardless of failures and shortcomings, the believer in Christ cannot be condemned to eternal hellfire because he has already been justified. This same double negative phenomenon is also used to express the permanency of salvation in Revelation 3:5, “He that overcometh, the same shall be clothed in white raiment; and I will not (author's italics) blot out his name out of the book of life, but I will confess his name before my Father, and before his angels.”